As the University examines the feasibility of building two new residential colleges, students and faculty are considering the implications of what could be the first significant increase in undergraduate enrollment since the 1960s.

An expansion could reduce dreaded housing crunches at the existing residential colleges, while academic departments would likely have to increase their faculty sizes in order to handle the larger student body — which could grow by at least 10 percent if two new colleges are created. Students, meanwhile, were largely critical of the colleges’ likely location, north of the Grove Street Cemetery, where the University recently swapped $10 million in local infrastructure improvements for development rights to three dead-end streets.

It is not clear whether the construction of two new colleges would be primarily intended to reduce crowding at the current 12 colleges or create room for an enlarged student body, said Dean of Administrative Affairs John Meeske, who has not yet been involved in the study.

“There’s been some talk in the past about … how much should be for relieving current pressure,” Meeske said. “Certainly, a lot of people are suggesting that should be done.”

The new residential colleges, if built to house roughly as many students as do the current 12, would allow for an increase in enrollment by about 800 to 900 students. But if the University is interested in adding only about 500 students — as Physics Department chair Ramamurti Shankar suggested to the News last week — the two new colleges could conceivably reduce or eliminate annexing by allowing the existing colleges to slightly decrease their populations.

About 360 students live in annexes around campus this year, Meeske said.

“In theory, we all would like to do away with annexes if we possibly could,” he said. “I think we all recognize that the first choice is for students to live in the residential colleges, and that’s the first choice for administrators as well.”

Even if the numbers work out, however, eliminating annexing would create new problems for freshman housing and for college masters and deans, Meeske said.

If smaller colleges no longer need to be filled beyond their physical capacities, the relative sizes of college student bodies could vary even more than they currently do. Smaller colleges, like Trumbull, could have as few as 80 freshmen, while larger colleges could have as many as 120 — a discrepancy which could place an unequal burden on the deans and masters of the larger colleges, Meeske said. This variation could also cause problems for matching residential colleges to Old Campus dorms, which are not designed to each neatly house extra-large or small populations.

Rachel Smith ’08, who is annexed this year in the Harrison Court apartments at 210 Park St. because Saybrook College ran out of housing, said she would be happy to see annexing end, especially for upperclassmen who have to live among freshmen on Old Campus.

“I think generally annexing sucks,” she said. “And if I were on Old Campus, I think I would be a lot less happy with my situation.”

But building new residential colleges might not be the best solution, Smith said.

“I’m kind of hesitant to embrace that idea,” she said. “It hasn’t happened for a half a century. It’s almost a tradition of having 12 [colleges]. And behind the Grove Street Cemetery seems a little far away.”

But Ying Xiao ’08, annexed in Vanderbilt because of a housing crunch in Berkeley, said he does not think annexing is much of an inconvenience and that it should not be the driving force behind building new residential colleges. Building new colleges — which would allow more students to come to Yale — is a positive step, Xiao said, but the colleges’ rumored location would be a major drawback.

“I think it’s a great idea as long as they’re not as ugly as Morse and Stiles,” he said.

Another complication is that additional students could strain Yale’s faculty, whose size has remained relatively constant over the last 15 years. The University’s student-to-teacher ratio, important to many prospective students as well as the U.S. News & World Report rankings, currently stands at seven to one.

Thomas Kavanagh, chair of the French Department, said that if the University does increase its enrollment, it will have to allow for a commensurate increase in faculty size across the board. Without hiring new faculty, he said, classroom education would suffer.

“There would be no way we could provide the same quality of instruction, particularly for language classes, where a lot of it has to do with class size,” Kavanagh said. “In all honesty, I must say the administration is aware of that.”

In the Chemistry Department, chair Gary Brudvig said, fluctuations in enrollment are not uncommon, as students’ interests change over time. In the last several years, he said, more Yalies have been interested in taking classes that would prepare them for medical school, which has led to an enrollment spike in his department. The department has had to adapt by scheduling more sections for labs and vying for space in lecture halls, Brudvig said, but he is happy with the result.

A permanent increase in enrollment, though, would be best addressed by adding faculty, Brudvig said.

“It would seem to me appropriate that if the size of Yale grows, that the number of faculty grows with it,” he said. “It may mean that some programs that are growing could grow even more, and that could push them beyond what they could accommodate.”

While some students said the location of the potential new colleges would make them too isolated, others pointed out that science students currently have long distances to travel between their housing and classes.

Bill Whitaker ’10, who lives in Swing Space, said people in his dorm feel removed, and that students living in new residences near Science Hill would have a similar problem.

But Allison Bruff ’10 said she views the proposed location as a welcome change for science students.

“It would be so convenient,” she said. “You wouldn’t have to hike all the way up Science Hill, which is so far away.”

In any case, Whitaker said, it would be in Yale’s best interest to expand the faculty if the student body grows.

“With 500 more students, it would be even harder to get into the more exclusive and interesting seminars,” Whitaker said.

In expanding, the University would be following the lead of its peers. Bolstered by the construction of Whitman College, Princeton University is in the midst of increasing its enrollment by 11 percent — from 4,700 to 5,200 — by the fall of 2012. Harvard University is in the first steps of its expansion into nearby Allston, Mass., a project that is likely to include additional undergraduate housing along the Charles River.